[lttng-dev] [BABELTRACE RFC PATCH] Parse LTTng indexes
Julien Desfossez
jdesfossez at efficios.com
Fri Aug 9 11:18:50 EDT 2013
If a trace file has an associated index (same filename and .idx suffix),
we open it and use it instead of generating the index at open.
Signed-off-by: Julien Desfossez <jdesfossez at efficios.com>
---
formats/ctf/ctf.c | 205 +++++++++++++++++++++++++++++++++++++++-
include/babeltrace/ctf/types.h | 1 +
include/lttng-index.h | 44 +++++++++
3 files changed, 245 insertions(+), 5 deletions(-)
create mode 100644 include/lttng-index.h
diff --git a/formats/ctf/ctf.c b/formats/ctf/ctf.c
index 947b439..6f1064b 100644
--- a/formats/ctf/ctf.c
+++ b/formats/ctf/ctf.c
@@ -35,6 +35,7 @@
#include <babeltrace/context-internal.h>
#include <babeltrace/compat/uuid.h>
#include <babeltrace/endian.h>
+#include <lttng-index.h>
#include <inttypes.h>
#include <stdio.h>
#include <sys/mman.h>
@@ -1666,6 +1667,148 @@ error:
return ret;
}
+static
+int import_stream_packet_index(struct ctf_trace *td,
+ struct ctf_file_stream *file_stream)
+{
+ struct ctf_stream_declaration *stream;
+ struct ctf_stream_pos *pos;
+ struct lttng_packet_index lttng_index;
+ struct lttng_packet_index_file_hdr index_hdr;
+ uint64_t packet_map_len = DEFAULT_HEADER_LEN;
+ struct packet_index index;
+ int ret, index_read;
+ int first_packet = 1;
+ size_t filesize;
+ struct stat filestats;
+
+ pos = &file_stream->pos;
+
+ ret = read(pos->index_fd, &index_hdr, sizeof(index_hdr));
+ if (ret < 0) {
+ perror("read index file header");
+ goto error;
+ }
+ /* Check the index header */
+ if (strncmp(index_hdr.magic, INDEX_MAGIC, sizeof(index_hdr.magic)) != 0) {
+ fprintf(stderr, "[error] wrong index magic\n");
+ ret = -1;
+ goto error;
+ }
+ if (be32toh(index_hdr.index_major) != INDEX_MAJOR ||
+ be32toh(index_hdr.index_minor) != INDEX_MINOR) {
+ fprintf(stderr, "[error] Incompatible index file %" PRIu64
+ ".%" PRIu64 ", supported %d.%d\n",
+ be64toh(index_hdr.index_major),
+ be64toh(index_hdr.index_minor), INDEX_MAJOR,
+ INDEX_MINOR);
+ ret = -1;
+ goto error;
+ }
+
+ while ((index_read = read(pos->index_fd, <tng_index,
+ sizeof(lttng_index)))) {
+ uint64_t stream_id;
+
+ index.offset = be64toh(lttng_index.offset);
+ index.packet_size = be64toh(lttng_index.packet_size);
+ index.content_size = be64toh(lttng_index.content_size);
+ index.timestamp_begin = be64toh(lttng_index.timestamp_begin);
+ index.timestamp_end = be64toh(lttng_index.timestamp_end);
+ index.events_discarded = be64toh(lttng_index.events_discarded);
+ stream_id = be64toh(lttng_index.stream_id);
+
+ if (first_packet) {
+ int len_index;
+
+ file_stream->parent.stream_id = stream_id;
+ stream = g_ptr_array_index(td->streams, stream_id);
+ if (!stream) {
+ fprintf(stderr, "[error] Stream %" PRIu64
+ " is not declared in metadata.\n",
+ stream_id);
+ ret = -EINVAL;
+ goto error;
+ }
+ file_stream->parent.stream_class = stream;
+ ret = create_stream_definitions(td, &file_stream->parent);
+ if (ret)
+ goto error;
+
+ ret = fstat(pos->fd, &filestats);
+ if (ret < 0)
+ goto error;
+
+ if (!filestats.st_size) {
+ fprintf(stderr, "[error] Empty trace file\n");
+ ret = -1;
+ goto error;
+ }
+ filesize = filestats.st_size;
+
+ if (filesize - pos->mmap_offset < (packet_map_len >> LOG2_CHAR_BIT)) {
+ packet_map_len = (filesize - pos->mmap_offset) << LOG2_CHAR_BIT;
+ }
+
+ if (pos->base_mma) {
+ /* unmap old base */
+ ret = munmap_align(pos->base_mma);
+ if (ret) {
+ fprintf(stderr, "[error] Unable to unmap old base: %s.\n",
+ strerror(errno));
+ return ret;
+ }
+ pos->base_mma = NULL;
+ }
+ /* map new base. Need mapping length from header. */
+ pos->base_mma = mmap_align(packet_map_len >> LOG2_CHAR_BIT, PROT_READ,
+ MAP_PRIVATE, pos->fd, pos->mmap_offset);
+ assert(pos->base_mma != MAP_FAILED);
+ /*
+ * Use current mapping size as temporary content and packet
+ * size.
+ */
+ pos->content_size = packet_map_len;
+ pos->packet_size = packet_map_len;
+ pos->offset = 0; /* Position of the packet header */
+
+ /* update trace_packet_header and stream_packet_context */
+ if (pos->prot != PROT_WRITE && file_stream->parent.trace_packet_header) {
+ /* Read packet header */
+ ret = generic_rw(&pos->parent, &file_stream->parent.trace_packet_header->p);
+ assert(!ret);
+ }
+ if (pos->prot != PROT_WRITE && file_stream->parent.stream_packet_context) {
+ /* Read packet context */
+ ret = generic_rw(&pos->parent, &file_stream->parent.stream_packet_context->p);
+ assert(!ret);
+ }
+ index.data_offset = pos->offset;
+
+ /* read events discarded len from header */
+ len_index = bt_struct_declaration_lookup_field_index(
+ file_stream->parent.stream_packet_context->declaration,
+ g_quark_from_static_string("events_discarded"));
+ if (len_index >= 0) {
+ struct bt_definition *field;
+
+ field = bt_struct_definition_get_field_from_index(
+ file_stream->parent.stream_packet_context,
+ len_index);
+ index.events_discarded_len = bt_get_int_len(field);
+ }
+ first_packet = 0;
+ }
+ /* add index to packet array */
+ g_array_append_val(file_stream->pos.packet_cycles_index, index);
+ }
+
+ ret = 0;
+
+error:
+ return ret;
+}
+
/*
* Note: many file streams can inherit from the same stream class
* description (metadata).
@@ -1675,9 +1818,10 @@ int ctf_open_file_stream_read(struct ctf_trace *td, const char *path, int flags,
void (*packet_seek)(struct bt_stream_pos *pos, size_t index,
int whence))
{
- int ret, fd, closeret;
+ int ret, fd, closeret, index_fd;
struct ctf_file_stream *file_stream;
struct stat statbuf;
+ char *index_name;
fd = openat(td->dirfd, path, flags);
if (fd < 0) {
@@ -1700,6 +1844,8 @@ int ctf_open_file_stream_read(struct ctf_trace *td, const char *path, int flags,
file_stream = g_new0(struct ctf_file_stream, 1);
file_stream->pos.last_offset = LAST_OFFSET_POISON;
+ file_stream->pos.fd = -1;
+ file_stream->pos.index_fd = -1;
strncpy(file_stream->parent.path, path, PATH_MAX);
file_stream->parent.path[PATH_MAX - 1] = '\0';
@@ -1722,19 +1868,60 @@ int ctf_open_file_stream_read(struct ctf_trace *td, const char *path, int flags,
* For now, only a single clock per trace is supported.
*/
file_stream->parent.current_clock = td->parent.single_clock;
- ret = create_stream_packet_index(td, file_stream);
- if (ret) {
- fprintf(stderr, "[error] Stream index creation error.\n");
- goto error_index;
+
+ /*
+ * Allocate the index name for this stream and try to open it.
+ */
+ index_name = malloc((strlen(path) + 4) * sizeof(char));
+ if (!index_name) {
+ fprintf(stderr, "[error] Cannot allocate index filename\n");
+ goto error_def;
+ }
+ sprintf(index_name, "%s.idx", path);
+
+ if (faccessat(td->dirfd, index_name, O_RDONLY, flags) == 0) {
+ index_fd = openat(td->dirfd, index_name, flags);
+ if (index_fd < 0) {
+ perror("Index file openat()");
+ ret = -1;
+ goto error_free;
+ }
+ file_stream->pos.index_fd = index_fd;
+ ret = import_stream_packet_index(td, file_stream);
+ if (ret) {
+ ret = -1;
+ goto error_index;
+ }
+ ret = close(file_stream->pos.index_fd);
+ if (ret < 0) {
+ perror("close index");
+ goto error_free;
+ }
+ } else {
+ ret = create_stream_packet_index(td, file_stream);
+ if (ret) {
+ fprintf(stderr, "[error] Stream index creation error.\n");
+ goto error_index;
+ }
}
+ free(index_name);
+
/* Add stream file to stream class */
g_ptr_array_add(file_stream->parent.stream_class->streams,
&file_stream->parent);
return 0;
error_index:
+ if (file_stream->pos.index_fd > 0) {
+ ret = close(file_stream->pos.index_fd);
+ if (ret < 0) {
+ perror("close index");
+ }
+ }
if (file_stream->parent.trace_packet_header)
bt_definition_unref(&file_stream->parent.trace_packet_header->p);
+error_free:
+ free(index_name);
error_def:
closeret = ctf_fini_pos(&file_stream->pos);
if (closeret) {
@@ -1761,6 +1948,7 @@ int ctf_open_trace_read(struct ctf_trace *td,
struct dirent *dirent;
struct dirent *diriter;
size_t dirent_len;
+ char *ext;
td->flags = flags;
@@ -1816,6 +2004,13 @@ int ctf_open_trace_read(struct ctf_trace *td,
|| !strcmp(diriter->d_name, "..")
|| !strcmp(diriter->d_name, "metadata"))
continue;
+
+ /* Ignore index files : *.idx */
+ ext = strrchr(diriter->d_name, '.');
+ if (ext && (!strcmp(ext, ".idx"))) {
+ continue;
+ }
+
ret = ctf_open_file_stream_read(td, diriter->d_name,
flags, packet_seek);
if (ret) {
diff --git a/include/babeltrace/ctf/types.h b/include/babeltrace/ctf/types.h
index 715cdbd..c64b8d2 100644
--- a/include/babeltrace/ctf/types.h
+++ b/include/babeltrace/ctf/types.h
@@ -61,6 +61,7 @@ struct packet_index {
struct ctf_stream_pos {
struct bt_stream_pos parent;
int fd; /* backing file fd. -1 if unset. */
+ int index_fd; /* backing index file fd. -1 if unset. */
GArray *packet_cycles_index; /* contains struct packet_index in cycles */
GArray *packet_real_index; /* contains struct packet_index in ns */
int prot; /* mmap protection */
diff --git a/include/lttng-index.h b/include/lttng-index.h
new file mode 100644
index 0000000..56f325a
--- /dev/null
+++ b/include/lttng-index.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2013 - Julien Desfossez <jdesfossez at efficios.com>
+ * David Goulet <dgoulet at efficios.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef LTTNG_INDEX_H
+#define LTTNG_INDEX_H
+
+#include <limits.h>
+
+#define INDEX_MAGIC "CTFIDX"
+#define INDEX_MAJOR 1
+#define INDEX_MINOR 0
+
+struct lttng_packet_index_file_hdr {
+ char magic[6];
+ uint32_t index_major;
+ uint32_t index_minor;
+} __attribute__((__packed__));
+
+struct lttng_packet_index {
+ uint64_t offset; /* offset of the packet in the file, in bytes */
+ uint64_t packet_size; /* packet size, in bits */
+ uint64_t content_size; /* content size, in bits */
+ uint64_t timestamp_begin;
+ uint64_t timestamp_end;
+ uint64_t events_discarded;
+ uint64_t stream_id;
+} __attribute__((__packed__));
+
+#endif /* LTTNG_INDEX_H */
--
1.7.10.4
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